This sounds a lot like the problem I was having with my servo. When I would start up EZ builder for the first time the servo what slam all the way to the end of the rotation then come back to the position I wanted. I talk about it in my project. I did find a workaround. visit my project pages and you'll see a discussed. it's almost towards the end. let me know if this helps.www.ez-robot.com/Community/Forum/posts.aspx?threadId=2263

@Dave, It seems that we have the same kind of problem. However, none of my servos have "1" as a min position, but have between "15" and "35".Here is a screenshot :

I have made some observations that maybe may help :

1/It happens only after a shutdown/power-up of the EZB, not after a simple deconnexion or closing of EZ-Builder.2/After Power-up, if I just load the project, connect to EZB and directly launch the following script :

If you set the speed before the init position, the servo is going to slowly move into the position you specified.

Also, keep in mind how a servo works. You can find more under the Tutorials section, I advise reading. It uses electrical pulses in a pulse to determine the position. When you power on and off the ez-b, electrical pulses are sent which are going to move the servo randomly. That is an inherit behaviour of the servo and how they work.

Do do you center yourservo to the 50 position before you attached your horn? That would be where EZI builder thanks center is. Then attach the horn to your neutral position. after you make sure that is the case set your minimum position to 50 and see what happens.

The other thing I did was built a switch circuit with a transistor in resistor in a diode. I used that circuit to turn on the power to the servo after the enable signal is sent from Ez builder. I attached the switching circuit to a digital port on EZ-B and used EZ builder to switch the transistor on and off. this is how I was able to smooth out the startup of the Servo. again, this is just the workaround I don't know why ez builder jumps to the absolute minimum settings that start up.

Let me know what happens. DJ did seem interested in this problem when I was talking about it in my thread.

@DJ, IT WORKED! The problem came from setting another servo speed than "0" before the init position.

I voluntarily set the speed before the init position, because i prefered to see the robot slowly move its arms and head to a neutral position at startup. The script by itself worked well, if not launched after a power on...

So, I clearly have missed something, because I don't understand why setting a slower speed induce a return of the servo to position "0", before moving to the defined position, and only after a power on.

Concerning the electrical pulse, I indeed observe it each time I power on the EZB and servos move to a random position, but very close to their previous position (before power on). What I observed could happens long after power on the EZB... It didn't change anything if I launched the script immediatly before power on or 10 minutes after.

In any case, you saved my day and Wall-E don't have its scary wierd behavior anymore. Thanks.

Thank you again DJ. first chance I get I need to redo my startup script so this won't happen to me anymore. thanks guys for bringing this up. my project keeps running better and better everyday thanks to this group.